Hydraulic striking devices of the general type shown in the present application have recently been constructed and sold by various manufacturers because of the economies of using liquid under pressure as compared with pneumatic devices using compressed air. A structure of similar type is shown in U.S. patent application serial No. 569,531, Salmi et al, filed Apr. 18, 1975, now U.S. Pat. No. 4,028,995 which apparatus includes a body having a cylinder space, a piston and cylinder structure axially movable therein, and a sleeve or liner-type distributing valve surrounding the movable piston and axially movable relative to the other component for controlling the action of the piston therein. As shown in that application, when the distributing valve is in its lowest position (nearest the tool end of the device) and the piston is in or near its lowest position, the liquid under pressure flows from a lower cylinder space through a canal in the piston to that portion of the distributing valve space which is defined by the body, the piston and the lower end of the distributing valve. Pressure is thereby applied to the distributing valve to move it to its upper position and that part of the distributing valve space is filled with liquid under pressure. When the piston moves to its upper position, the liquid under pressure escapes from that part of the distributing valve space through the piston canal into an outlet canal. It is possible to utilize this escaping oil for rotating the rotating motor of a drilling machine as shown in U.S. patent appliation Ser. No. 649,679, Salmi, filed Jan. 17, 1976 now U.S. Pat. No. 4,039,033. However, in devices wherein the oil is not utilized for some other purpose, it is simply wasted. Because the amount of the wasted liquid under pressure in the apparatus shown in application Ser. No. 569,531 is relatively large, this is a disadvantage of the construction described in that application.